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DocLightning
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Thrust Reversers Before Touchdown?

Tue Jul 08, 2008 5:29 am

Check out this video:

http://www.youtube.com/watch?v=VIGtAjjnQbs&feature=related

Look at the thrust reverser deployment. Now, the wheels are CLEARLY off the ground when he deploys them.

Other than "he's a crazy Rusky" why would you do this?
-Doc Lightning-

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jetstar
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RE: Thrust Reversers Before Touchdown?

Tue Jul 08, 2008 10:09 pm

It looks like they just deployed the thrust reversers, probably landing on a short runway to get them extended and ready for thrust reverse application as soon as they touch down. Normally as soon as you pull up on the thrust reverser levers, the reversers will extend, but it takes pulling up on the reverser levers to increase engine thrust to make the reversers effective.

On the Lockheed JetStar we occasionally did this landing on a short runway, there was no weight on wheels switch or auto reverse thrust, as long as the power levers were back to idle we could deploy the reversers, so as soon as we pulled the throttle levers back to idle just before touch down we extended the reverser buckets and were ready to apply reverse thrust.

Turbine jet engines can have a few second lag from the time of reverser deployment to full reverse thrust, so by getting the reverser buckets out early and even pulling up on the thrust reverser levers the engines would start spooling up and by the time the wheels touched down, enough reverse thrust would be available to start slowing the airplane down as max thrust reverse was applied
 
2H4
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RE: Thrust Reversers Before Touchdown?

Tue Jul 08, 2008 10:15 pm

Here are some relevant photos:


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Photo © Raymond Wang
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Photo © Howard Chaloner




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Photo © Miguel Claudio
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Photo © Jose Geraldes



Quoting Jetstar (Reply 1):
Turbine jet engines can have a few second lag from the time of reverser deployment to full reverse thrust, so by getting the reverser buckets out early and even pulling up on the thrust reverser levers the engines would start spooling up and by the time the wheels touched down, enough reverse thrust would be available to start slowing the airplane down as max thrust reverse was applied

I wonder if such a procedure is officially approved and/or recommended in any flight manuals...

2H4
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 12:11 am



Quoting DocLightning (Thread starter):

Other than "he's a crazy Rusky" why would you do this?

As evidenced by the pics this doesn't seem to be an uncommon procedure on the type. I remember Gabon Express did the same on their Caravelle.

The question, as 2H4 says, is if this is approved in the manual.
"There are no stupid questions, but there are a lot of inquisitive idiots."
 
2H4
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 12:38 am



Quoting Starlionblue (Reply 3):
The question, as 2H4 says, is if this is approved in the manual.

Actually, this thread could become very interesting......does anyone here know of a procedure that, while approved in the flight manual, is in your opinion unsafe or unwise?

The only I can think of off the top of my head are rather extreme flap settings in some older 172s and 182s that make landings a bit dodgy when operating at light weights. I think the combination of full flaps and light weights have set a lot of pilots up for nosewheel-first landings over the years.

2H4
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Sasha
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 12:45 am

Seems to be a common thing at least in Russia. Yak 40, Tu 154 and IL62 deploy thrust reverse whenever landing in challending weather conditions to avoid risk of runway overrun (slippery surface etc).
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Viscount724
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 1:09 am

The DC-8 is also certified for inflight use of thrust reversers. I recall several previous threads in this forum referring to that.
 
jetstar
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 2:36 am



Quoting 2H4 (Reply 2):
I wonder if such a procedure is officially approved and/or recommended in any flight manuals...

If I remember correctly, deploying the thrust reversers before wheels touching down was not in the JetStar flight manual, but also there was no prohibition in the manual about not doing it, so I guess it’s a gray area. Also I am only talking about the legacy P&W powered JetStar, not the 731 varsion.
 
wilco737
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 3:59 am

Some aircrafts are certified to use the thrust reverser before touchdown. On most aircraft the thrust reverser won't be operable until the air/ ground sensor on the wheels senses ground. Like on the MD11F. Only when the main wheels are on the ground you will be able to activate the thrust reverser. And thrust reverser number two will only be available for full thust reverse once the nose gear is on the ground (MD11F). Sometimes you see eng #1 and #3 on full reverse and #2 is still on its way to full reverse  Wink

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Starlionblue
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 8:57 am



Quoting Viscount724 (Reply 6):
The DC-8 is also certified for inflight use of thrust reversers. I recall several previous threads in this forum referring to that

Yes but not on final approach.  Wink

Quoting WILCO737 (Reply 8):
Like on the MD11F. Only when the main wheels are on the ground you will be able to activate the thrust reverser. And thrust reverser number two will only be available for full thust reverse once the nose gear is on the ground (MD11F). Sometimes you see eng #1 and #3 on full reverse and #2 is still on its way to full reverse

I'm guessing that if #2 deploys before nose wheel touch down there will be a rotating moment in the wrong direction, keeping the nose wheel up longer than wanted.
"There are no stupid questions, but there are a lot of inquisitive idiots."
 
wilco737
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 9:04 am



Quoting Starlionblue (Reply 9):
I'm guessing that if #2 deploys before nose wheel touch down there will be a rotating moment in the wrong direction, keeping the nose wheel up longer than wanted.

When the main wheels touchdown, all three thrust reverser can be engages in idle. You can move the thrust lever to full reverse thrust, but the FADEC will keep eng #2 at idle reverse until the nose gear is on the ground. then it spools up to full reverse thrust.
And about the moment you are right. To avoid a pitch up moment during or right after touchdown, it is designed like this. Same with the spoilers. with main gear touchdown they come out 2/3rd and with nose gear touchdown they move to full extend...

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XT6Wagon
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 9:45 am

The 737-400 is able to deploy the reversers w/o the wheels down, it uses the radar altimiter to allow/deny the use of the reversers.
 
David L
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 1:26 pm



Quoting Viscount724 (Reply 6):
The DC-8 is also certified for inflight use of thrust reversers.

As was the HS Trident. It could achieve a decsent rate of ~10,000 fps if necessary, though the FE apparently had to work very hard to regulate the cabin pressure. From memory, I'm pretty sure it was approved on Concorde, too.
 
CosmicCruiser
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 2:09 pm



Quoting Jetstar (Reply 7):
If I remember correctly, deploying the thrust reversers before wheels touching down was not in the JetStar flight manual, but also there was no prohibition in the manual about not doing it



Quoting Jetstar (Reply 7):
Also I am only talking about the legacy P&W powered JetStar, not the 731 varsion.

Yea, I flew both versions of the Jetstar for about 3 years and we never deployed the reversers prior to tochdown and I don't remember it ever being discussed in grd. school at Marietta nor Flight Safety but then I speaking of 35 yrs ago!!  old 
 
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 2:53 pm



Quoting XT6Wagon (Reply 11):
The 737-400 is able to deploy the reversers w/o the wheels down, it uses the radar altimiter to allow/deny the use of the reversers.

Are you saying B734.
Why not Air-Grd sense.
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DocLightning
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 6:32 pm

Quoting Jetstar (Reply 1):
Normally as soon as you pull up on the thrust reverser levers, the reversers will extend, but it takes pulling up on the reverser levers to increase engine thrust to make the reversers effective.

I'm sorry, but this sentence makes no sense. You state that you pull up on the reverser levers to extend the reversers... but then that the same action, yet somehow different, will cause the engines to spool up? I think you made a typo and since I've never flown a plane, I'm not sure what you mean.

Could you kindly clarify?

Quoting David L (Reply 12):
As was the HS Trident. It could achieve a decsent rate of ~10,000 fps if necessary, though the FE apparently had to work very hard to regulate the cabin pressure.

Why is that?

So my other question is that if you deploy the reversers before you cross the threshold and then you get hit by a gust of wind that throws your roll off or something, how are you going to get them stowed in time to do a go-around? He looked to be a good 10 feet AGL when they folded out. And in 2H4's photos, it appears that they are as much as 30-40 ft. AGL with reversers deployed. I know probably nobody here has every flown a Tu-154, but is it really THAT much of a bulldozer to stop?

[Edited 2008-07-09 11:38:18]
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wilco737
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 6:35 pm



Quoting DocLightning (Reply 15):
Could you kindly clarify?

he means: you pull on the thrust reverser lever. Then the thrust reverser will be activated, means the doors for the T/R start to open and the flow of the thrust will be reversed. But only idle. During this door opening you can pull on the T/R levers as much as you want, you cannot move them up any further. means you only have idle reverse thrust until the doors are fully opened, then this lock will be removed and you can pull on the T/R levers and adjust it from idle reverse to full reverse...

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LY744
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 7:20 pm

Deploying T/R before touchdown is standard procedure on the IL-62 (where only 2 of the engines have reversers), but I'm not aware of that being part of the Tu-154 SOPs. Of course nothing that a modern Tu-154/Il-86/Il-76/An-12/Tu-134/Il-62 crew does could surprise me anymore.


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point8six
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RE: Thrust Reversers Before Touchdown?

Wed Jul 09, 2008 7:41 pm

Reverse in the air , above 10,000ft, was approved for the HS Trident, as was full reverse in the flare (for short/wet/contaminated runways). I believe it was used on Concorde to reduce speed from supersonic to subsonic. I understand it was used on DC-8s with RR Conways - not sure about other engine types. I have seen it selected in the flare on a B747-400 - fortunately it did not deploy until "weight-on"  Wow!
 
David L
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 1:09 am



Quoting DocLightning (Reply 15):
Why is that?

The example I heard (on TV) was from an ex-Trident Captain who was given an approach slot that required either descending that quickly or joining the back of a long queue. It certainly wasn't routine.  Smile

Quoting DocLightning (Reply 15):
how are you going to get them stowed in time to do a go-around?

Good point. As Starlionblue says, I'm not aware of the other types mentioned deploying reversers at the same point as those Il-62 examples.

Quoting Point8six (Reply 18):
I believe it was used on Concorde to reduce speed from supersonic to subsonic.

Not routinely, though?
 
tdscanuck
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 6:19 am



Quoting 2H4 (Reply 2):
I wonder if such a procedure is officially approved and/or recommended in any flight manuals...

It's allowed on all 737NG's from the factory...whether an airline puts that into their flight manuals is another question.

Quoting Viscount724 (Reply 6):
The DC-8 is also certified for inflight use of thrust reversers. I recall several previous threads in this forum referring to that.

Most low-bypass engines with bucket-reversers can be safely deployed in flight without a disaster happening. For high bypass engines with cascade or petal reversers, it's generally a bad thing so it's usually restricted to being on the ground or very close to it (at least on Western aircraft).

Quoting XT6Wagon (Reply 11):
The 737-400 is able to deploy the reversers w/o the wheels down, it uses the radar altimiter to allow/deny the use of the reversers.

All 737NG's can do this too.

Quoting HAWK21M (Reply 14):
Are you saying B734.
Why not Air-Grd sense.

You always want two air/ground inputs to make sure you don't loose reversers if an air/ground sensor goes bad. On Boeing's with multi-axel bogies, they use strut compression and truck tilt as the two inputs. 737's, for obvious reasons, don't have a truck tilt sensor. So they used the radio altimeter as the other input. You can deploy reversers if you're on the ground or if the radio altitude is less than 10'.

Tom.
 
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 9:32 am



Quoting 2H4 (Reply 4):
The only I can think of off the top of my head are rather extreme flap settings in some older 172s and 182s that make landings a bit dodgy when operating at light weights. I think the combination of full flaps and light weights have set a lot of pilots up for nosewheel-first landings over the years.

Take it easy there, Astronaut; the 40 degree flap settings on the early Cessna singles were wonderful if one flew into short or rough runways, especially if one had to dive-bomb over tall trees near the approach end of a short field.

The 182 on landing is nose-heavy, even with NO flaps,
and can be wheelbarrowed by the novice quite easily.
 
nomadd22
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 11:29 am

Maybe he was an old Harrier pilot having a flashback.
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 2:16 pm



Quoting ThirtyEcho (Reply 21):
Take it easy there, Astronaut; the 40 degree flap settings on the early Cessna singles were wonderful if one flew into short or rough runways, especially if one had to dive-bomb over tall trees near the approach end of a short field.

Hey, no argument here! I've had plenty of fun with flaps40.  yes 

My point was simply that, over the years, that flap setting has set many less-than-disciplined pilots up for very bad days. To them, it's just another flap setting. In reality, it's an introduction to a very different set of benefits and pitfalls...all of which should be considered and respected.

Quoting ThirtyEcho (Reply 21):
The 182 on landing is nose-heavy, even with NO flaps,
and can be wheelbarrowed by the novice quite easily.

Precisely!

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mark5388916
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 4:30 pm

The C-5 Galaxy Also can deploy T/Rs in flight. IIRC, Its limited to FL240 when the T/Rs are out of service because it won't be able to descend fast enough otherwise..

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avioniker
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RE: Thrust Reversers Before Touchdown?

Thu Jul 10, 2008 7:02 pm



Quoting Starlionblue (Reply 9):
I'm guessing that if #2 deploys before nose wheel touch down there will be a rotating moment in the wrong direction, keeping the nose wheel up longer than wanted.



Quoting WILCO737 (Reply 10):
And about the moment you are right. To avoid a pitch up moment during or right after touchdown, it is designed like this. Same with the spoilers. with main gear touchdown they come out 2/3rd and with nose gear touchdown they move to full extend...

You have both brought up a once popular misconception.
Actually it's to keep the nose from slamming down as a result of the heavy deceleration and turning the plane into a big bananna.
Think of the mass forward of the CG on landing. It's going forward and down, it isn't going to easily change direction and go up to allow the tail to drag. With three engines rated over 60Klbs and about 40% of that available in reverse you'd have potentially 80Klbs of reverse thrust available if all three engines spooled up on main touchdown. With a plane weighing in at about 490K and more than half of that forward of the CG the nose is coming down with any deceleration of the total mass.
Douglas demonstrated it in 1978 and again inn 1985 for the Air Force on the DC10 and they bent a frame in Yuma in 1992 using triple reverse with the nose in the air.
The only way to drag the tail in a 10 or 11 is to be so slow on final that you have the nose too high trying to keep flying or to be way too fast and over rotate.
That's basic.
 Smile
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kalvado
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RE: Thrust Reversers Before Touchdown?

Fri Jul 11, 2008 5:18 pm



Quoting David L (Reply 12):
As was the HS Trident. It could achieve a decsent rate of ~10,000 fps if necessary

should it be 10 000 fpm? 3000 m/s is way too hypersonic..
 
Bellerophon
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RE: Thrust Reversers Before Touchdown?

Fri Jul 11, 2008 10:08 pm



Quoting Point8six (Reply 18):
Reverse in the air, above 10,000ft, was approved for the HS Trident

Reverse in the air, right down to touchdown, was approved on the Trident. There was no only above 10,000 ft restriction. Having said that, it was very rarely used on approach.

However, the use of reverse idle, or even reverse thrust, in the flare, once the thrust levers had been closed, was very common.

Quoting Point8six (Reply 18):
I believe it was used on Concorde to reduce speed from supersonic to subsonic.

No, it was not approved for use whilst supersonic, only when subsonic.

Quoting David L (Reply 12):
As was the HS Trident. It could achieve a decsent rate of ~10,000 fps if necessary,

Small typo I suspect, I think you meant 10,000 fpm !

Quoting David L (Reply 12):
though the FE apparently had to work very hard to regulate the cabin pressure.

It did cause some problems, as the cabin would have to be set to descend at a much greater rate than normal.

As no negative pressure differential could be tolerated (as would occur if the aircraft altitude became lower than cabin altitude) if, during a rapid descent, the aircraft altitude ever reached the cabin altitude, then they would have to give up, and let the cabin descend at the same rate as the aircraft.  Wink

On both the Trident and Concorde, the principal value, and best use, of reverse thrust was the ability to reduce speed very quickly, in a shallow descent, whilst keeping the aircraft attitude (and so the cabin floor) substantially level.

Where possible, this was a much better use of reverse thrust than using it to achieve very high rates of descent, at constant speed, with the consequent large nose down pitch attitudes, which could alarm cabin crew, never mind passengers.

If a runaway bar trolley, dragging a stewardess behind it, thumped into the flight deck door, you had probably overdone the nose down attitude!  Silly


Best Regards

Bellerophon
 
nomadd22
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RE: Thrust Reversers Before Touchdown?

Fri Jul 11, 2008 10:39 pm



Quoting Bellerophon (Reply 27):
Small typo I suspect, I think you meant 10,000 fpm !

Dang. I was looking forward to that 7,000mph decent.
Anon
 
point8six
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 7:56 am

There was a restriction on the use of reverse thrust on the HS Trident, during descent and it was a SOP restriction, that it had to be cancelled by FL 100. Full reverse was approved in the flare. Of course it didn't stop some from using reverse "illegally" to help out on a "hot" approach Big grin . The reason I remember the SOP restriction is that I once had both reversers jam at reverse idle, having cancelled reverse at FL100 (which was confirmed by the FDR, much to the disappointment of the Engineering Managers on the "Inquisition" board).  Wow!
 
2H4
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 2:53 pm



Quoting Point8six (Reply 29):
There was a restriction on the use of reverse thrust on the HS Trident, during descent and it was a SOP restriction, that it had to be cancelled by FL 100.

Sorry, I'm not quite clear on this....was the restriction put in place by the manufacturer, or by the airline?

Quoting Point8six (Reply 29):
The reason I remember the SOP restriction is that I once had both reversers jam at reverse idle, having cancelled reverse at FL100

Well heck, don't leave us hanging...what's the rest of the story? I assume you eventually got them stowed, but how long did it take? What was found to be responsible for the problem? Sounds like one heck of a story!  yes 

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Blackbird
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 5:14 pm

I think it's pretty obvious that the Trident could do a 10,000 feet per minute descent, not 10,000 feet a second.


Andrea Kent
 
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 7:14 pm

T/R before touchdown, if an FS2004 manual for a Tu-154M is of any value whatsoever (please do note a raised eyebrow on my part) is supposedly discretionary. I've flown on a few Tupolevs (Tu-154B, M, and -134A-3) and I have to say that the landings were on the whole very smooth indeed, with none of the velcro-esque resticking that Western jets do - of course, there is the old chestnut about 'flying a Boeing onto the ground' and not 'landing' it - though I suppose this is something to do with the wide track of the Tupolev undercarriages in comparison to their Airbus and Boeing counterparts.

A couple of the touchdowns were preceded by a sudden change of noise behind the cabin and a slight decelaration, and it was certainly nowhere near as crazy a manoeuvre as the fools posting on YouTube would have one believe... The Estonian landing in the video appears wholly normal from having observed some approaches at LED.

Quoting Blackbird (Reply 31):
I think it's pretty obvious that the Trident could do a 10,000 feet per minute descent, not 10,000 feet a second.

I took him at his word - after all, the Trident was a pioneer in many respects... First full autoland, first non-centred nosewheel, and those are just two off the top of my head...  Wink

Toni
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David L
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 8:30 pm



Quoting Kalvado (Reply 26):
Quoting David L (Reply 12):
As was the HS Trident. It could achieve a decsent rate of ~10,000 fps if necessary

should it be 10 000 fpm? 3000 m/s is way too hypersonic..



Quoting Bellerophon (Reply 27):
Small typo I suspect, I think you meant 10,000 fpm !

10,000 feet per Saturday. What's wrong with that? On the other hand... oops!  duck 

Quoting Bellerophon (Reply 27):
Where possible, this was a much better use of reverse thrust than using it to achieve very high rates of descent

Indeed, I've only heard that one example of the use of reverse for such a rapid descent, albeit at only 1/60th of the rate I stated.  embarrassed 
 
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DocLightning
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 9:53 pm



Quoting WILCO737 (Reply 16):
he means: you pull on the thrust reverser lever. Then the thrust reverser will be activated, means the doors for the T/R start to open and the flow of the thrust will be reversed. But only idle. During this door opening you can pull on the T/R levers as much as you want, you cannot move them up any further. means you only have idle reverse thrust until the doors are fully opened, then this lock will be removed and you can pull on the T/R levers and adjust it from idle reverse to full reverse...

Aha. Thanksey.

Quoting Blackbird (Reply 31):
I think it's pretty obvious that the Trident could do a 10,000 feet per minute descent, not 10,000 feet a second.

I bet it could do 10,000 feet per second. You aim the nose straight down and select full thrust. Pretty soon...

...you win a Darwin Award!  duck 
-Doc Lightning-

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Bellerophon
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RE: Thrust Reversers Before Touchdown?

Sat Jul 12, 2008 11:39 pm

Point8six

There was a restriction on the use of reverse thrust on the HS Trident, during descent and it was a SOP restriction, that it had to be cancelled by FL 100.


BEA / BA imposed two main limitations on the use of reverse thrust in the air, both listed in the Operations Manual - Volume 1 – Flight Management - Engines (ATPs 661/861/961).
  • Not to be used above 365/350 kts IAS
  • Not to be used below 2,000 ft above terrain
There was no restriction, or SOP, prohibiting the use of reverse thrust below 10,000 ft.

If you still believe otherwise, perhaps you could be kind enough to cite your source or reference?


I once had both reversers jam at reverse idle

Which, if not cleared quickly, would have led to a double engine shut down and a single engine approach and landing! Ops Man Vol 1 (Flt Mgmt) - Engines refers.

To the best of my knowledge, BEA / BA never had a single engine landing on a Trident, so presumably the baulks cleared in your incident, but are you able to provide us with any more details about this incident?


Best Regards

Bellerophon
 
point8six
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RE: Thrust Reversers Before Touchdown?

Sun Jul 13, 2008 5:09 pm

Bellerophon - you obviously still have your Trident manuals -( mine are probably still in the loft of a house I moved from nearly 30 years ago!) and so your references regarding the use of reverse thrust must be taken as accurate.
The incident happened on a HS Trident 1C at the beginning of July 1976 (one of the hottest summers on record), on a flight from LHR to GLA. After a runway change from 24 to 06 at GLA, the a/c was high on the profile and full speedbrakes and reverse thrust on Engines 1+3 was used. Having succeeded in losing height and speed to regain the profile, reverse and then speedbrakes were cancelled. The a/c then glided down onto the glide slope and flaps and landing gear deployed. Shortly after land flap was selected, the handling co-pilot stated that he was unable to move 1+3 throttles from the idle position. At that point, with only No2 engine at approach power, a single -engine approach would not have been possible ( hot conditions and at near max. landing weight). After repeated and very forceful hits on No 1 throttle, it sprung open and the Captain applied full power to Engines 1 +2 and commenced a go-around, during which I managed to free No 3 throttle. The go-around and subsequent approach and landing were completed without further incident. The a/c was declared AOG, safety reports filed and we returned to LHR, flying a different a/c. Later on that day, I was phoned at home and asked if I would kindly go back to LHR as the Flight Manager wished to chat with me about the incident. The other 2 crew members were also present and the 'chat' turned out to be a "Spanish Inquisition", consisting of a board of 3 pilot managers and 2 engineer managers ( who opened the discussion with the words " there is nothing wrong with the a/c, it must be the way the crew used reverse thrust all the way down"!). The debate became quite heated until one of the pilot managers left the room briefly and then returned with a transcript of the FDR. At this point, he declared that our reports matched the FDR exactly and it was time for the engineers to go find the problem. It turned out to be an error in setting the tolerances for the baulk between forward and reverse thrust. An interesting problem, solved not by skill and experience, but by sheer brute force and ignorance!
Cancelling reverse by FL100 was mentioned several times during the "Inquisition", which is why I have made reference to it as an SOP.
After that incident, I resolved to have some sort of independent representation with me if I was to be summoned for a 'chat with management', following any incident. I am happy to say that I never had to resort to doing just that, except for seeking legal advice and action, when a Nigerian passenger filed a lawsuit for US $75 million against me in a New York Court - but that's another story  Smile
 
David L
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RE: Thrust Reversers Before Touchdown?

Sun Jul 13, 2008 5:58 pm



Quoting Point8six (Reply 36):
but that's another story

We're sitting comfortably.. you may begin.  biggrin 
 
JoeCanuck
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RE: Thrust Reversers Before Touchdown?

Sun Jul 13, 2008 7:51 pm

I saw a show that descent reverse thrust is available on the C-17.
What the...?
 
tdscanuck
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RE: Thrust Reversers Before Touchdown?

Mon Jul 14, 2008 5:42 am



Quoting JoeCanuck (Reply 38):
I saw a show that descent reverse thrust is available on the C-17.

It wouldn't surprise me...the C-17 can do a lot of things that a commercial jet can't do, primarily to achieve the desired short field performance.

Tom.
 
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Starlionblue
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RE: Thrust Reversers Before Touchdown?

Mon Jul 14, 2008 6:36 am



Quoting JoeCanuck (Reply 38):
I saw a show that descent reverse thrust is available on the C-17.

It is. By using idle reverse and deployed surfaces the C-17 can descend at 15000 fpm if memory serves.
"There are no stupid questions, but there are a lot of inquisitive idiots."
 
Bellerophon
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RE: Thrust Reversers Before Touchdown?

Mon Jul 14, 2008 2:40 pm

Point8six

Thanks for the detailed reply, I'm glad it was you and not me, as it must have been quite worrying for a while.

The impartial management investigation that followed sounds only too familiar...March in the guilty party, we have to listen to his excuses before we can pass sentence...I could probably make a good guess at some of the names involved!


...Cancelling reverse by FL100 was mentioned several times during the "Inquisition", which is why I have made reference to it as an SOP...

Well......

Having now discussed it with one or two of the few remaining Trident pilots in BA, I have to admit that you are not the only person who remembers this as an SOP.

I don't, and I still can't find any reference to it in any of the manuals, but perhaps it was, or perhaps it was a training recommendation, or possibly a variation between the T1/T2 and T3 fleets. Anyway, my apologies if I was overly dogmatic on this point.   


...you obviously still have your Trident manuals...

Er...yes! Guilty as charged.

And until recently, still occasionally flew the last Trident sim, (T3 – G-AWZQ) which is in private ownership and based near Biggin Hill.


Best Regards

Bellerophon

[Edited 2008-07-14 07:46:38]
 
point8six
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RE: Thrust Reversers Before Touchdown?

Tue Jul 15, 2008 8:29 am

You flew the Trident simulator voluntarily, until recently? I'm sending the men in white coats around. Big grin

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